240 M. YOKOYAMA. 



.si;st.^ of :i thif'k oom])lox of sandstone-!, cltiy-sl'itcs iind shnles, witli 

 subordinate layers of sclmlstciii and autlirncite in it.s lower ])art :ind 

 of brownco:d in its u])])er p'U't. These strata wliieli form a low 

 hilly country surrounded 1)\' niount-nns of u'ranite and of l^alaeozoic 

 formation strike generalh' from east to west, and show steeper dips in 

 the northern than in the southern part of the district, where they 

 gently .slope towards the sea. Owing to the repeated foldings to 

 whicli these strata luive heen subjected, their geoL^gicid structure is 

 complicated, and hns not yet been clearly mnde out. It will be 

 onlv added here th:it our fossils were discovered in the lower or 

 ^•cha]stein-l)enriijg ])ai't of this formati(^/n. 



The fossil locality lies on one side of a rond wliich lends from the 

 village of Yamanoi to the town of Habu, in a valley surrounded l)y 

 liills. Here in a space of al)out 4 meters, I observed four fossil horizons. 

 The loAvest of them is a yellowish o-rey aru'illnceous sandstone vieldins" 

 ini]y Dietyopliyllum japom'cum, ])ut in great numljers. The plants of 

 tliis horizon are easily (hstiuguishal)le from those of the others, being 

 coloured dark green as if the veget:d)le matter were still remaining (^n 

 tliem. Tlie next horizon is that of a light greyish argillaceous sand- 

 stone wliich on weathering also assumes a yellowish colour. In this 

 horizon all the species below described were found, ]\Ir. K<!cliii)e's 

 plants ha\ ing been probably taken also from this layer. Tlie two 

 iij)per horizons have yielded only some fragments of DiclyopJiylhim 

 japonicwn. I>esides tliese two lu^'izons there is, I ])resume, another, 

 as I ibund some jnnniv of the snme species in a black slate situated 

 more to tlie nortli and occupying |)r(jl)ablv a higlier ])osition than the 

 yaridstorjes. From this, we can see tliat there are several fossiliferous 

 zones in tlie coal-liearing series of Xagato. Uut at present as the 

 iiumber of species found in them is very small, it is not possible to 

 fiiake any palaeontological distinctions in them. 



